User Manual

Mobile Hydraulics Bosch Rexroth AG
RE 95 340/11.04 CEMA CAN Expansion Module
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Function
CAN Communication
The CAN expansion module provides the control unit that
is controlling the hydraulic drive with additional inputs and
outputs. The first control unit works as the master and the CAN
expansion module as the slave.
The CAN expansion module can send and receive messages:
• Send messages: The CAN expansion module reads the
values that are present at its inputs and sends this scaled
raw data to the master.
• Receive message: The CAN expansion module receives the
setpoints for its outputs sent by the master and actuates the
outputs accordingly.
• In addition to the input values, status information for the
outputs is also reported to the master.
Inputs/Outputs
Various inputs can be used twice. This usage is specified by
the master in the first receive message after a reset.
The following inputs and outputs are available:
Inputs/Outputs Value range Maximum
number
Analog
voltage inputs
0 to 5 V 4
Analog current inputs 0 … 20 mA 2
Switch inputs low < 1.5 V
high > 4.5 V
8
Frequency inputs 0 … 10 kHz
> 1 V
rms
3
PWM outputs 0 … 2.3 A
100 Hz, 200 Hz
2
Switch outputs Max. 2 A 2
Safety Functions
The CAN expansion module expects a CAN telegram from
the master at least once every 200 ms. If this telegram is
not received, the CAN expansion module shuts down all its
outputs and attempts to re-establish communication with the
master via the CAN bus.
The outputs are monitored for wire breaks and short circuits.
Their status is reported to the master.
Important Features
• The inputs and outputs of the control unit are monitored
(wire breaks, short circuit). Any faults are signaled to the
master.
• If CAN communication fails, the outputs are shut down.
• Any faults that occur are logged in the control unit and can
be read later on using BODEM or BB-3 in plain text.
Main Setting Variables
• CAN baud rate and format
• CAN IDs used
• Repeat rate for sent CAN telegrams
• Frequency of proportional outputs